RU2464533C2 - Very high frequency vibratory flow metre - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: very high frequency vibratory flow metre (100) has a flow metre assembly (10) and metre electronics (20). The flow metre assembly (10) includes one or more flow conduits (103A, 103B) and is configured to generate very high frequency response which is higher than a predetermined maximum decoupling frequency for the flowing fluid independent of the size of foreign material or composition of foreign material. The decoupling ratio (A_p/A_f) is approximately 3:1 for entrained gas at the very high frequency and approximately equal to 3/(1+(2* p_p/p_f)) for entrained solids at very high frequency. The decoupling ratio (A_p/A_f) is the ratio of the particle amplitude (A_p) to the fluid amplitude (A_f), where p_p is the particle density of foreign material, and p_f is density of the flowing fluid. The metre electronics (20) is connected to the flow metre assembly (10) and is configured to receive the very high frequency vibrational response and generate one or more flow measurements therefrom.

EFFECT: high accuracy and reliability of measuring flow rate of multiphase fluids.

24 cl, 4 dwg

Description

State of the art

1. The technical field

The present invention relates to a vibratory flow meter and, more particularly, to a vibratory flow meter with a very high vibration frequency.

2. Problem statement

Vibration flow meters, such as Coriolis mass flow meters and vibratory densitometers, typically operate by sensing the movement of a vibrating flow line that contains a flowing or non-flowing fluid. The characteristics associated with the material in the flow pipe, such as mass flow, density, etc., can be determined by processing the measurement signals received from displacement sensors associated with the flow pipe. Vibrational modes of a vibrating system filled with material usually depend on the total mass, rigidity, and damping parameters of the filled flow pipe and the material contained in it.

A typical vibratory flow meter includes one or more flow lines that connect to a line or other transport system and transport material, such as fluids, sludges, and the like, in the system. A flow line can be considered as a system having a number of eigenmodes, including, for example, simple bending, torsional, radial, and coupled modes. Typically, for measurements, the flow pipe is excited in one or more vibrational modes when the material flows through the flow pipe, and the movement of the flow pipe is detected at points spaced along the flow pipe. The excitation is usually provided by a drive, for example an electromechanical device, such as an induction drive operating at sound frequencies, which periodically perturbs the flow pipe. The density of the fluid can be obtained by determining the resonant frequency of the flowing fluid. Mass flow can be determined by measuring the time delay or by the phase difference between the movements at the locations of the sensors. Two such sensors (or strain gauges) are typically used to measure the vibrational response of a flow pipe or flow pipes and are usually located upstream and downstream of the drive. Two load cells are connected to the electronic measuring device using a cable, for example using two independent pairs of wires. The measuring device receives signals from two load cells and processes the signals to obtain a mass flow measurement.

Flow meters are used to measure mass flow and / or density measurements with a wide variety of flowing fluids and provide high accuracy for single-phase flows. One application of vibratory flow meters is to measure oil and gas output from a well. The product of such wells may contain a multiphase flow including liquids, but also include gases and / or solids that may be involved in the fluid flow. The fluid stream from the oil field may therefore include oil, water, air or other gases, and / or sand or other soil particles, for example. However, when a vibratory flow meter is used to measure a flowing fluid including entrained gases and / or solids, the accuracy of the meter may be significantly impaired. It is highly desirable that the final measurement be as accurate as possible, even for such multiphase flows.

Multiphase flowing fluids may include entrained gases, especially gas bubble flows. Multiphase flows may include solids involved or solids involved, mixtures, for example concrete, etc. In addition, multiphase flows may include liquids of various densities, for example, water and oil components. Phases can have different densities, viscosities, or other properties.

In a multiphase flow, vibration in the flow line does not necessarily move the gases / solids involved precisely in phase with the flowing fluid. This vibrational anomaly is referred to as separation or lag. Gas bubbles, for example, can separate from the flowing fluid, affecting the vibrational response and any subsequently obtained flow parameters. Small bubbles usually move with leaking fluid when the flowmeter vibrates. However, large bubbles do not move with the flowing fluid during vibration of the flow line. Instead, the bubbles can separate from the flowing fluid and can move independently, with the involved gas bubbles moving further and faster than with the flowing fluid at each vibrational displacement. This adversely affects the vibrational response of the flowmeter. This is also true for solids involved in a flowing fluid, in which solids are more likely to separate from the movement of the flowing fluid with increasing particle sizes or vibrational frequencies. Separation can occur even when the multiphase flow includes liquids of varying densities and / or viscosities. It has been found that the separation depends on various factors, such as the viscosity of the flowing fluid and the difference in the density of the flowing fluid and foreign material, for example.

In addition to the problems caused by the relative movement of bubbles and particles, Coriolis meters can have poor accuracy due to effects related to the speed of sound (SOS) or compressibility, when the speed of sound of the measured fluid is low or the frequency of the meter is high. Liquids have higher sound velocities than gases, but the lowest sound velocity values are obtained for their mixture. Even a small amount of gas involved in a liquid leads to a significant decrease in the speed of sound of the mixture; below that for any of the phases.

The oscillation of the flow tube produces sound waves that propagate in the transverse direction at the frequency of the meter drive. When the speed of sound for a fluid is high, as in a single-phase fluid, the first acoustic mode for transverse sound waves across a circular flow conduit corresponds to a much higher frequency than the frequency of the drive. However, when the speed of sound drops due to the addition of gas to the liquid, the frequency of the acoustic mode also drops. When the frequencies of the acoustic mode and the drive mode are close, meter errors occur due to non-resonant excitation of the acoustic mode by the drive mode.

For low-frequency meters and typical pressures used, the effects of sound velocity are present in multiphase flows, but they are usually insignificant at a given accuracy of the meter. However, for high-frequency Coriolis meters operating at low pressures with fluid with bubbles, the speed of sound can be low enough to cause significant measurement errors due to the interaction between the drive mode and the vibrational modes of the fluid.

The size of the bubbles can vary depending on the amount of gas present, the pressure of the flowing fluid, the temperature and the degree of mixing of the gas with the flowing fluid. The level of decrease in operating parameters is determined not only by how much gas is available as a whole, but also with the size of individual gas bubbles in the stream. Bubble size affects measurement accuracy. Large bubbles occupy a larger volume and, increasing, separate, leading to fluctuations in the density and measured density of the flowing fluid. Due to gas compressibility, bubbles can change gas content or mass without necessarily changing in size. Conversely, if the pressure changes, the size of the bubble can accordingly change, expanding when the pressure drops or contracting when the pressure increases. It can also cause variations in the natural or resonant frequency of the flowmeter.

Prior art vibratory flow meters have typically been designed for operating frequencies of approximately 100-300 Hz (Hz), and some meters have operated at frequencies of 500-1000 Hz. Some prior art meters have been designed to operate at higher frequencies. The operating frequency of the vibratory flow meter in the prior art is usually chosen so as to facilitate the design of the flow meter, its manufacture and its operation. For example, a vibratory, or Coriolis, flow meter in the prior art has been configured to be physically compact and substantially uniform in size. For example, the height of the flow meter in the prior art is usually less than the length, giving a small characteristic height to length ratio (H / L) and a corresponding high drive frequency. Flow meter users prefer a small overall size to simplify installation. In addition, the design of the flowmeter typically involves a uniform flow of a single-phase fluid and is designed to work optimally with such a uniform flowing fluid.

A direct flow meter has a zero characteristic height to length ratio, which usually results in a high drive frequency. Curved flow pipes are often used to avoid the prevalence of lengths and to increase the characteristic height to length ratio (H / L). A curved or bent pipeline flow meter in the prior art may have a characteristic height to length ratio approaching 1.3, for example.

In the art, there remains a need to obtain a vibratory flow meter that is suitable for accurate and reliable flow measurement of multiphase fluids.

SUMMARY OF THE INVENTION

In one aspect of the invention, a vibration meter with a very high vibration frequency comprises:

a flowmeter assembly including one or more flow lines with a flowmeter assembly configured to generate a vibration response with a very high frequency that is higher than a predetermined maximum separation frequency for the flowing fluid, regardless of the size of the foreign material or the composition of the foreign material; and

meter electronics connected to the flowmeter assembly and configured to receive a vibration response at a very high frequency and generate one or more measurements of flow parameters from it.

Preferably, the meter electronics is configured so that the separation ratio (A _p / A _f ) is approximately 3: 1 for the involved gas at a very high frequency.

Preferably, the meter electronics is configured so that the separation ratio (A _p / A _f ) is approximately equal to 3 / (1+ (2 * ρ _p / ρ _f )) for the solids involved at a very high frequency.

Preferably, the meter electronics is configured so that the viscosity is effectively zero with respect to particle movement for the flowing fluid at a very high frequency.

Preferably, a very high frequency has a value higher than about 1500 Hertz (Hz).

Preferably, the vibrational response with a very high frequency corresponds to the inverse of the Stokes number (δ), which is less than about 0.1.

Preferably, a very high frequency has a value higher than about 2000 Hertz (Hz).

Preferably, one or more flow pipes is configured to achieve a very high frequency by configuring one or more of the following parameters: rigidity of the flow pipe, length of the flow pipe, characteristic ratio of the flow pipe, material of the flow pipe, thickness of the flow pipe, shape of the flow pipe, geometry flow pipe or one or more positions of the vibrational nodes.

Preferably, the vibration meter with a very high vibration frequency is configured to operate at a frequency of the first bending mode.

Preferably, the vibration meter with a very high vibration frequency is configured to operate at higher order bending mode frequencies.

In one aspect of the invention, a method of operating a vibratory flowmeter with a very high vibration frequency comprises:

vibration of one or more flow lines of a vibratory flowmeter with a very high vibration frequency at a very high frequency that is higher than a predetermined maximum separation frequency for the flowing fluid, regardless of the size of the foreign material or the composition of the foreign material;

receiving a vibration response with a very high frequency; and

generating one or more flow measurements from a vibration response with a very high frequency.

Preferably, the meter electronics is configured so that the separation ratio (A _p / A _f ) is approximately 3: 1 for the involved gas at a very high frequency.

Preferably, the meter electronics is configured so that the separation ratio (A _p / A _f ) is approximately equal to 3 / (1+ (2 * ρ _p / ρ _f )) for the solids involved at a very high frequency.

Preferably, the meter electronics is configured so that the viscosity is effectively zero with respect to particle movement for the flowing fluid at a very high frequency.

Preferably, a very high frequency has a value higher than about 1500 Hertz (Hz).

Preferably, the very high frequency vibrational response corresponds to the inverse of the Stokes number (δ), which is less than about 0.1.

Preferably, a very high frequency has a value higher than about 2000 Hertz (Hz).

Preferably, one or more flow lines of a vibratory flowmeter with a very high vibration frequency is configured to achieve a very high frequency by configuring one or more of the following parameters: rigidity of the flow pipe, length of the flow pipe, characteristic ratio of the flow pipe, material of the flow pipe, thickness of the flow pipe pipe, flow pipe shape, flow pipe geometry, or one or more positions vibrational nodes.

Preferably, the vibration meter with a very high vibration frequency is configured to operate at a frequency of the first bending mode.

Preferably, the vibration meter with a very high vibration frequency is configured to operate at higher order bending mode frequencies.

In one aspect of the invention, a method of forming a vibratory flow meter with a very high vibration frequency comprises:

determining a predetermined very high frequency for the vibratory flow meter based on at least the expected flowing fluid, the very high frequency being higher than the preset maximum separation frequency for the flowing fluid, regardless of the size of the foreign material or the composition of the foreign material;

Configuring a vibratory flowmeter with a very high vibration frequency to operate at a very high frequency; and

design of a vibratory flowmeter with a very high vibration frequency.

Preferably, the meter electronics is configured so that the separation ratio (A _p / A _f ) is approximately 3: 1 for the involved gas at a very high frequency.

Preferably, the meter electronics is configured such that the separation ratio (A _p / A _f ) is approximately 3 / (1+ (2 * ρ _p / ρ _f )) for the solids involved at a very high frequency.

Preferably, the meter electronics is configured so that the viscosity is effectively zero with respect to particle movement for the flowing fluid at a very high frequency.

Preferably, a very high frequency has a value higher than about 1500 Hertz (Hz).

Preferably, the very high frequency vibrational response corresponds to the inverse of the Stokes number (δ), which is less than about 0.1.

Preferably, a very high frequency has a value higher than about 2000 Hertz (Hz).

Preferably, one or more flow pipes is configured to achieve a very high frequency by configuring one or more of the following parameters: rigidity of the flow pipe, length of the flow pipe, characteristic ratio of the flow pipe, material of the flow pipe, thickness of the flow pipe, shape of the flow pipe, geometry flow line or one or more positions of the vibrational nodes.

Preferably, the vibration meter with a very high vibration frequency is configured to operate at frequencies of the first bending mode.

Preferably, the vibration meter with a very high vibration frequency is configured to operate at higher order bending mode frequencies.

Description of drawings

The same numerals in the drawings correspond to the same elements. It should be borne in mind that the drawings are not necessarily made to scale.

Figure 1 depicts a vibratory flow meter with a very high vibration frequency in accordance with the invention.

Figure 2 is a diagram of the results of modeling the total density error for a very low-frequency mode and a very high-frequency mode of the Coriolis flowmeter model Micro Motion E200.

Figure 3 is a vibration meter with a very high vibration frequency in accordance with an embodiment of the invention.

4 is a flowchart of a method of operating a very high frequency vibratory flow meter in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

The accompanying Figures 1-4 and the following description show specific examples for those skilled in the art, explaining how to implement and use the best embodiment of the invention. In order to explain the principles of the invention, some ordinary objects are simplified or omitted. Those skilled in the art will appreciate the obvious variations of these examples that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. Thus, the invention is not limited to the specific examples described below, but is limited only in accordance with the formulas and their equivalents.

1 shows a vibratory flowmeter 5 with a very high vibration frequency in accordance with the invention. A very high vibration frequency flow meter 5 in one embodiment comprises a Coriolis flow meter. In another embodiment, the vibration meter 5 with a very high vibration frequency comprises a vibratory densitometer.

Vibration flowmeter 5 with a very high vibration frequency is designed to measure the parameters of the flowing fluid, including measuring the parameters of the flowing fluid in either dynamic or stationary modes. The vibratory flow meter 5 with a very high vibration frequency is furthermore designed to accurately and reliably measure the parameters of the flowing fluid when the flowing fluid contains multiple phases. In some embodiments, the multiphase flowing fluid may include entrained gas, the entrained gas may contain a stream of bubbles. The entrained gas may include air bubbles or bubbles of various sizes. The gas involved created problems in prior art vibratory flow meters. The entrained gas, especially in the case of medium and large bubbles, can move independently of the flowing fluid and cause measurement errors or uncertainties. In addition, the entrained gas can cause measurement ambiguity due to the compressibility of the gas, which varies with the change in the working pressure of the flowing fluid.

In some embodiments, the multiphase flowing fluid may include solids involved, wherein the solids involved may contain sludge. One example contains particles of sand or soil in an oil stream. The solids involved can move independently of the flowing fluid and lead to measurement errors and / or uncertainties. Another example is concrete. Other sludges or emulsions are also intended as part of the description and the appended claims.

In some embodiments, the multiphase flow may include different liquids, for example immiscible liquids, which cannot be mixed together. For example, a leaking fluid may include both water and oil. When the components of the flowing fluid have different densities, the components of the flowing fluid may experience some separation during vibration of the flow meter. Foreign objects may be less dense than leaking fluid. Foreign objects may be denser than leaking fluid.

In operation, the vibratory flowmeter 5 with a very high vibration frequency vibrates at a very high frequency. A very high frequency may comprise a first flexural vibrational mode. Alternatively, a very high frequency may comprise a second, third or higher order bending mode of vibration. However, other vibrational modes are also possible, for example, oscillations outside the resonance, and they are meant in the framework of the description and the attached formula. As a result, the vibratory flow meter 5 with a very high vibration frequency generates a vibration response with a very high frequency. A very high frequency vibrational response is processed to determine either the response frequency, or the amplitude of the response, or both. A very high response frequency can be used to determine one or more parameters of the flowing fluid, including mass flow rate, density, viscosity, and so on. The essence of the flowmeter 5 with a very high vibration frequency is discussed further below.

The flowmeter 5 includes a flowmeter assembly 10 and meter electronics 20. The meter electronics 20 is connected to the meter assembly 10 via wires 100 and configured to provide measurement results for one or more of the following parameters — density, mass flow rate, volumetric flow rate, total mass flow rate, temperature and other information via channel 26 communications. It will be clear to those skilled in the art that the present invention can be used for any type of vibratory flow meter, regardless of the number of drives, strain gauges, flow lines, or operating vibration mode. It should be noted that the flowmeter 5 may comprise a vibrating densitometer and / or a Coriolis mass flowmeter.

The flowmeter assembly 10 includes a pair of flanges 101 and 101 ', manifolds 102 and 102', a drive 104, strain gauges 105 and 105 ', and flow lines 103A and 103B. An actuator 104 and strain gauges 105 and 105 ′ are connected to flow lines 103A and 103B.

In one embodiment, the flow conduits 103A and 103B comprise substantially U-shaped flow conduits, as shown. Alternatively, in other embodiments, the conduits may comprise substantially straight flow conduits. However, other forms may also be used, and they are meant in the framework of the description and the attached formulas.

Flanges 101 and 101 'are attached to manifolds 102 and 102'. Manifolds 102 and 102 'may be attached to opposite ends of the spacer 106. The spacer 106 maintains the gap between the manifolds 102 and 102' to prevent unwanted vibrations in the flow lines 103A and 103B. When the flowmeter assembly 10 is inserted into a piping system (not shown) that transfers the measured flowing fluid, the flowing fluid enters the flowmeter assembly 10 through the flange 101, passes through the inlet manifold 102, where all the flowing fluid is directed to the inlet of the flow pipelines 103A and 103B, flows through the flow lines 103A and 103B and back to the outlet manifold 102 ', where it leaves the measuring assembly 10 through the flange 101'.

Flow lines 103A and 103B are selected and mounted respectively on the inlet manifold 102 and on the outlet manifold 102 'so as to have substantially the same mass distribution, moments of inertia, and elastic moduli around the bending axes W - W and W' - W ', respectively. Flow lines 103A and 103B extend outwardly from manifolds 102 and 102 'in a substantially parallel manner.

The flow lines 103A and 103B are driven by the actuator 104 in opposite directions around the respective bending axes W and W 'and the so-called first non-phase bending mode of the flowmeter 5. However, the flow lines 103A and 103B can alternatively vibrate in a second or higher bending mode, if desired. The actuator 104 may include one of many known devices, for example, a magnet mounted on a flow line 103A, and an opposing coil mounted on a flow line 103B. An alternating current passes through the opposing coil, causing both flow pipes to oscillate. The corresponding exciting signal is supplied by the electronics of the meter 20 to the actuator 104 through the wire 110.

The meter electronics 20 receives sensor signals over wires 111 and 111 ', respectively. The electronics of the meter 20 produces an exciting signal on the wire 110, which through the actuator 104 causes the flow lines 103A and 103B to oscillate. The meter electronics 20 processes the left and right speed signals from the strain gauges 105 and 105 'to calculate the mass flow rate. The communication channel 26 provides input and output, which provide the interface of the electronic meter 20 with the operator or with other electronic systems. The description of FIG. 1 is provided solely as an example of the operation of a vibratory flowmeter and should not be a fundamental limitation of the present invention.

Figure 2 shows a graph of the results of modeling the total density error with a very low frequency mode and a very high frequency mode of the Coriolis flowmeter model Micro Motion E200. It can be seen that for very small particle sizes, any separation is negligible, for example, when the separation ratio (A _p / A _f ) is approximately unity and the density error is therefore negligible. In this small particle scenario, the effects of sound velocity (SOS) / compressibility dominate. As a result, the high-frequency mode has a positive error and the low-frequency mode does not have a large error at all.

However, when the bubbles become more than a few tenths of a millimeter in diameter, the separation effects begin to dominate the SOS / compressibility effects, and the error is negative. It should be noted that if the particle size increases, the observed error will asymptotically tend to results for an inviscid model, that is, to a value of approximately 3: 1 for the separation ratio (A _p / A _f ). This asymptotic behavior also manifests itself in connection with the size of the bubble, when the oscillation frequency is high. Therefore, if the meter oscillates at a sufficiently high frequency, then equation (14) can be used. Equation (14) is independent of the size of the bubble and the viscosity of the flowing fluid.

3 shows a vibratory flowmeter 5 with a very high vibration frequency in accordance with an embodiment of the invention. A very high frequency may be based on the effective length of one or more flow lines 103A, 103B and the geometry of the flowmeter 5, as previously indicated. The effective length in some implementations can be controlled by the geometry of the flow pipe. In addition, the drive frequency can be further changed by one or more balanced masses, which can then be attached to one or more flow lines 103A, 103B, if necessary.

In the drawing, the flowmeter 5 has a large length L with respect to a small height H. The vibrational flowmeter 5 has a very high vibration frequency, therefore, it can have a small characteristic height-to-length ratio (H / L). For example, the characteristic height to length ratio (H / L) may be less or much less than unity. Therefore, the flowmeter 5 with a very high vibration frequency in accordance with the invention is relatively small and therefore easily adapted for most measuring applications.

In some embodiments, a very high frequency comprises a vibration frequency above 1500 Hz. In some embodiments, a very high frequency comprises a vibration frequency above 2000 Hz. In some embodiments, a very high frequency comprises a vibration frequency above 3000 Hz and above. However, it should be understood that the vibration frequency can be any frequency above these threshold values, if the required very high frequency will ultimately depend on various factors, including the composition of the flowing fluid and the nature of the foreign material involved, for example.

FIG. 4 shows a flowchart 400 of a method of operating a vibratory flowmeter with a very high vibration frequency in accordance with the invention. At step 401, the flowmeter oscillates at a very high frequency. A very high frequency may include a frequency when the separation ratio (A _p / A _f ) is about 3: 1 for the gas involved. A very high frequency may include a frequency when the separation ratio (A _p / A _f ) is approximately 0: 1 for the solids involved at a very high frequency. A very high frequency may include a frequency as the code achieves approximately zero effective viscosity for the flowing fluid. A very high frequency may include a frequency when a very high frequency has a value that is higher than a predetermined maximum separation frequency, regardless of the size of the foreign material or the composition of the foreign material. A very high frequency may include a frequency when a very high frequency has a value that is above a predetermined maximum SOS / compressibility threshold, regardless of the size of the foreign material or the composition of the foreign material. A very high frequency may include a frequency that is above about 1500 Hertz (Hz). A very high frequency may include a frequency that is above about 2000 Hertz (Hz).

One or more flow lines of a vibratory flowmeter with a very high vibration frequency is configured to achieve a very high frequency by configuring one or more of the following parameters: stiffness of the flow pipe, length of the flow pipe, separation ratio of the flow pipe, material of the flow pipe, thickness of the flow pipe, the shape of the flow pipe, the geometry of the flow pipe, or one or more positions of the vibration units, as reviewed earlier.

A vibration meter with a very high vibration frequency can be configured to operate on the first bending mode. A vibration meter with a very high vibration frequency can be configured to operate on one or more bending modes, for example, second or third bending modes, or higher order bending modes.

At 402, a vibrational response of the flowmeter assembly is received. A vibrational response can be used to determine the resulting frequency and amplitude, including a frequency that may contain a resonant frequency for the flowing fluid, or a non-resonant frequency.

At 403, one or more flow measurements can be made from the vibration response at a very high frequency. One or more flow measurements may include mass flow. One or more flow measurements may include density. A density measurement using a very high frequency can be determined with assumptions regarding the separation ratio and fluid viscosity. Other flow measurements are considered and are within the scope of the description and the attached formulas.

The drive frequency is the frequency at which one or more flow lines 103A and 103B oscillate to measure flow parameters of a flowing fluid. The drive frequency may be chosen to be a resonant frequency for the flowing fluid, for example, or may contain one or more harmonics of the resonant frequency, higher order bending mode frequencies, or even non-resonant frequencies. Therefore, the drive frequency may differ from the vibrational response frequency received from the flowmeter assembly 10, and may vary in accordance with the composition of the flowing fluid. In addition, the drive frequency depends on the rigidity of the flowmeter. With increasing stiffness parameters, the drive frequency also increases. As a result, an increase in the rigidity of the flow pipe will result in a higher resonant frequency of the flow pipe and, therefore, an increase in the frequency of the flow meter. The rigidity of the flow pipe can be increased in various ways, as discussed below.

A very high oscillation frequency can be achieved by oscillating the assembly 10 of the flowmeter in the first bending mode. The first bending mode contains the resonant frequency of the assembly 10 of the flow meter, and the length of the flow pipe is shifted in a single direction. Alternatively, a very high oscillation frequency may include oscillation of the flowmeter assembly 10 in a second bending mode. In the second bending mode on the flow pipe, there are additional vibration nodes near the center of the vibrating section of the flow pipe. The sections of the flow pipe on both sides of this vibration unit are displaced in opposite directions.

In some embodiments, a very high frequency vibration meter 5 can operate at a very high frequency as a result of the design of the meter. In some embodiments, a very high frequency vibration meter 5 can operate at a very high frequency as a result of a drive signal configuration.

The consequence of the multiphase of the flowing fluid is that accurate fluid measurements are difficult during such characteristic periods of multiphase. Multiphase effects may be present even in the presence of moderate to medium multiphase flow conditions. The features of a multiphase flowing fluid can be manifested in compressibility / sound velocity (SOS) effects and in the effects of separation between the components of a multiphase flowing fluid. Two effects can be controlled or they can be eliminated by proper selection of the frequency and amplitude of the oscillations.

Multiphase flowing fluids may include entrained gases, especially gas bubble flows. Multiphase flows may include solids involved or solids involved, mixtures such as concrete, sludge, etc. In addition, multiphase flows may include liquids of various densities, such as water and oil components, for example. The phases may have different masses, densities and / or viscosities.

In a multiphase flow, the vibration of the flow line does not necessarily move the gases / solids involved completely in phase with the flowing fluid. This vibrational anomaly is referred to as separation or lag. Gas bubbles, for example, can become separated from the flowing fluid, affecting the vibration response and any subsequent flow parameters. Small bubbles usually move with leaking fluid when the flowmeter vibrates. However, large bubbles do not move with the flowing fluid during vibration of the flow line. Instead, the bubbles can be separated from the flowing fluid and can move independently, with the involved gas bubbles moving further and faster than the flowing fluid during each oscillatory movement. This adversely affects the vibrational response of the flowmeter. This is also true for solids involved in a flowing fluid, when solids are more likely to separate from the movement of the flowing fluid with increasing vibration frequencies. Separation may even occur when the multiphase flow includes liquids of varying densities and / or viscosities. It has been found that separation is influenced by various factors, such as viscosity of the flowing fluid and differences in the density of the flowing fluid and foreign material, for example.

The size of the bubbles may vary depending on the amount of gas present, pressure of the flowing fluid, temperature, degree of mixing of the gas in the flowing fluid, and other flow properties. The level of performance degradation is associated not only with how much total gas is present, but also with the size of individual gas bubbles in the stream. Bubble size affects measurement accuracy. Large bubbles occupy a larger volume, leading to fluctuations in the density and measured density of the flowing fluid. Due to the compressibility of the gas, the bubbles can vary in mass and not necessarily change in size. Conversely, if the pressure changes, the size of the bubble may accordingly change, expanding if the pressure drops, or contracting, with increasing pressure. It can also cause a change in the natural or resonant frequency of the flowmeter.

In a vibrating flow pipe, acceleration of the vibrating flow pipe causes the bubbles to move. The acceleration of the flow pipe is determined by the frequency and amplitude of the oscillations. In the case of entrained gas, the bubbles are accelerated in the same direction as the acceleration of the flow pipe. Bubbles move faster and farther than the flow line, and the bubble moves faster, and the resulting fluid displacement causes a certain amount of fluid to move more slowly than the flow line, causing a true shift of the center of gravitational attraction of the fluid mixture from the center of the vibrating flow line. This is the basis of the separation problem. As a result, the flow and density parameters are underestimated (negative flow and density errors) when the air involved is present.

Sludge is a similar problem. In the case of sludge, however, solid particles are often heavier than the liquid component. When accelerating a vibrating flow line, heavier particles move less than liquid. But since heavy particles move less, the center of gravity of the fluid mixture still moves slightly back from the center of the flow pipe. This again leads to negative flow and density errors.

In gas-liquid cases, solid-liquid and liquid-liquid, the different motion of the involved phase is caused by the difference in the density of the involved phase and the liquid component. If gas compressibility is neglected, then the same equations can be used to describe the behavior of all three scenarios.

Compensating fluid separation was difficult because there are several factors that determine how much bubbles move relative to the fluid. Fluid viscosity is an obvious factor. In a very viscous fluid, bubbles (or particles) are effectively frozen in place in the fluid, and a small error occurs for the flow parameters. At a very low oscillation frequency, the flowing fluid will act as a very viscous fluid, that is, as if the viscosity were infinite. At a very high oscillation frequency, the flowing fluid will act as an inviscid fluid, that is, as if the viscosity were approximately zero.

Viscosity is a measure of the resistance of a fluid that is deformed, either by shear stress or tensile stress. Typically, this is resistance to fluid flow, a quantitative assessment of fluid viscosity. Viscosity can be considered as a measure of fluid internal friction. All real fluids have some compression resistance, but a fluid that has no resistance to shear stress is considered an ideal fluid or an inviscid fluid.

Also, bubble size is affected by bubble size. The hydrodynamic resistance of the bubble is proportional to the surface area, while the buoyancy force is proportional to the volume. Therefore, very small bubbles have a large ratio of hydrodynamic resistance to buoyancy and can move with the fluid. Small bubbles, respectively, lead to small errors. Conversely, large bubbles may not move with the fluid and lead to large errors. The same is true for solid particles, as small particles can move with the fluid and cause only small errors.

Another problem caused by vibration is the speed of sound (SOS) or compressibility effects. These effects make mass flow and density measurements for streams with a gas content more and more inaccurate as the vibration frequency increases.

The difference in density is another factor. The buoyancy force is proportional to the difference in density of fluid and gas. The high pressure gas may have a density high enough to influence the buoyancy force and reduce the separation effect. In addition, large bubbles occupy a larger volume, leading to true fluctuations in the density of the flowing fluid. Due to the compressibility of the gas, the bubbles can vary in the amount of gas and it is not necessary to change in size. Conversely, if the pressure changes, the size of the bubble can accordingly change, expanding when the pressure drops, or contracting when the pressure increases. It can also cause a change in the natural or resonant frequency of the flow meter and, thus, a change in the actual two-phase density.

Second order factors can also have an effect on bubbles and particle mobility. Turbulence at high fluid flow rates can break large gas bubbles into smaller ones, thereby reducing the separation error. Surfactants reduce the surface tension of the bubbles and reduce their tendency to coalesce. Valves can reduce the size of the bubble by increasing turbulence, while the bends of the flow line can increase the size of the bubble by compressing them by centrifugal force.

It should be understood that the most common, least difficult, and least expensive approach is to avoid multiphase flowing fluids. However, this is not always practical or possible. The approach considered here is not to avoid multiphase separation and SOS / compressibility effects, but instead a flowmeter operation is proposed in which a known and substantially constant measurement error occurs. As a result, flow measurements are simplified and measurement errors can subsequently be removed.

It has been found that separation effects can reach an upper limit. This upper limit provides previously unattainable benefits. For example, if the flowing fluid oscillates at a sufficiently high frequency, then the separation effect will reach a predictable upper limit. It was found that for the gas involved at very high vibrational frequencies, the separation effect will not be more than approximately 3: 1, that is, the gas bubble will move three times further compared to the movement of the liquid component. It was found that for the solids involved at very high vibrational frequencies, the separation effect will be approximately equal to 3 / (l + (2 * ρ _p / ρ _f )). If the density of the solid particle is much higher than the density of the liquid, then the involved solid particles will be essentially stationary, while the liquid component moves with the vibration of the flow pipe.

Compressibility will not apply to solids involved. Therefore, a very high frequency vibrational flowmeter 5 can oscillate at a frequency equal to or greater than the upper limit frequency for separation. Any resulting SOS / compressibility effects can be compensated for using conventional techniques.

The upper limit may be independent of the size of the flow pipe, shape or geometry. The upper limit may be independent of the liquid component. The upper limit may primarily depend on the ratio of the densities of the liquid component and the foreign material.

The advantages of using a very high frequency vibratory flowmeter 5 with a very high vibration frequency can be achieved using appropriate design parameters. One approach to creating a vibratory flowmeter 5 with a very high vibration frequency is to increase the frequency of the drive signal. This can be done regardless of the resonant frequency of flowmeter 5. For example, flowmeter 5 can operate on higher order bending modes.

Another approach to creating a vibratory flowmeter 5 with a very high vibration frequency is that the rigidity of the meter should be increased in order to increase the operating frequency and / or resonant (or natural) frequency along with the amplitude of the flow pipe. The rigidity of the meter can be increased in any way. However, some possible options are discussed below.

A factor affecting the rigidity of the meter is the length of the flow pipe. The length of the flow meter essentially correlates with the stiffness of the meter, with a decrease in the length of the meter leads to some increase in the stiffness of the meter and the operating frequency. Accordingly, the length of the flow meter can be selected so as to achieve at least some increase in the rigidity of the meter.

A factor affecting the rigidity of the meter is the characteristic ratio of the flow pipe. In this case, the characteristic ratio of the flow meter is defined as the height of the flow meter (H) divided by the length of the flow meter (L) and the characteristic ratio = (H / L) (see FIG. 3). If the height (H) is less than the length (L), the characteristic ratio of height to length (H / L) will be less than one. If the flowmeter is a direct flowmeter, the characteristic height to length ratio (H / L) will be effectively zero. If the height (H) is greater than the length (L), the characteristic ratio of height to length (H / L) will be greater than one. For example, in the flow meter 5 in FIG. 2, the characteristic height to length ratio (H / L) will be significantly larger than unity and may reach a relatively large value. The decrease in the characteristic ratio of height to length (H / L) leads to an increase in the stiffness of the meter and the resonant frequency of the meter. Thus, the characteristic ratio of height to length (H / L) can be selected so as to at least achieve some increase in stiffness of the meter.

A factor affecting the rigidity of the meter is the material of the flow pipe. The material of the flow pipe can be selected so as to at least achieve some increase in the rigidity of the meter and a corresponding increase in the oscillation frequency.

A factor affecting the rigidity of the meter is the thickness of the flow pipe. The thickness of the flow pipe can be increased to achieve at least some increase in the rigidity of the meter. The thickness of the flow pipe can be increased in any suitable way. However, substantially substantial increases in the thickness of the flow pipe can lead to an increase in weight.

A factor affecting the rigidity of the meter is the shape of the flow pipe. The shape of the flow pipe can be designed to achieve at least some increase in the rigidity of the meter. The shape of the flow conduit can be modified in any desired manner, including the use of flow conduits of substantially circular, elliptical, rectangular, irregular shape, or other suitable shapes.

A factor affecting the rigidity of the meter is the geometry of the flow pipe. The geometry of the flow pipe can be designed to achieve at least some increase in the rigidity of the meter. The geometry of the flow pipe can be selected in any desired way, including the use of appropriate straight and curved sections, for example. For example, a U-shaped flow line has less rigidity than a straight flow line of a flowmeter of the same length and the same type.

A factor affecting the frequency of the meter is the mass of the flow pipe. The resonant frequency of the assembly 10 of the flow meter increases if the mass of the flow pipe decreases. The mass of the flow pipe can be reduced in any desired manner, including the use of lighter flow pipes.

A factor affecting the rigidity of the meter is the nodal throttle of the flow pipe and the location of the vibration nodes. The flowmeter assembly 10 may include one or more nodal chokes that control the position of the oscillation unit and therefore affect the bending axis and vibration response. A conventional nodal choke in the illustrated embodiment comprises a spacer 106 in combination with manifolds 102 and 102 '. Alternatively, in other implementations, the nodal choke may comprise one or more tightening brackets that are rigidly located between two flow lines at a certain point substantially adjacent to flanges 101 and 101 ', i.e., substantially at two ends of the flowmeter 5 (not shown). One or more node chokes are included to lock the vibration nodes of the curved flow lines 103A and 103B, creating the desired bending axes. One or more nodal chokes can be placed so as to reduce the length of the flow lines that experience vibration, thereby increasing the resonant frequency of the vibration meter 5 with a very high vibration frequency.

As a result of the precise design of the meter, the vibration meter 5 with a very high vibration frequency can operate at very high frequencies. Operation at a very high frequency results in separation maintained with a separation ratio of approximately 3: 1 for the gas involved or approximately 3 / (l + (2 * ρ _p / ρ _f )) for the solids involved. In addition, operating at a very high frequency gives flow parameters similar to a flow in which the viscosity is effectively zero. As a result, the foreign material in the multiphase fluid flow moves in a predictable manner relative to the liquid component of the flowing fluid. This is true whether the foreign material contains gas or solid components. This is true whether the foreign material has a moderately different density relative to the flowing fluid or whether the foreign material has a very different density. As a result, the foreign material involved will not significantly affect the measurements made by the vibratory flowmeter 5 with a very high vibration frequency after the predicted errors due to separation and SOS / compressibility effects are removed. In addition, the vibratory flowmeter 5 with a very high vibration frequency is consistent and predictably immune to variations in the fraction of gas voids (GVF) and / or the fraction of solids and is suitable for satisfactory measurement of flowing fluid, even when the composition of the multiphase flowing fluid changes, as discussed below in connection with equations (13-19).

The meter electronics 20 generate an excitation signal for the actuator 104 and can be configured to excite / oscillate the meter assembly 10 at a very high frequency. As in the usual practice of using vibratory flowmeters, the electronics of the meter 20 in this case produces an exciting signal of a given frequency, and the specified frequency can be controlled and modified by a feedback signal taken from strain gauges. For example, the drive signal may be controlled in accordance with feedback to achieve a resonant (i.e., natural) vibrational response frequency as measured by strain sensors 105 and 105 '. The electronics of the meter 20 can be configured to operate on higher order bending modes.

The meter electronics 20 can be configured to create a very high frequency in various ways. The electronics of the meter 20 can be configured during the manufacturing process, for example by programming a memory device for the electronics of the meter 20. Alternatively, the electronics of the meter 20 can be configured at a very high frequency during the calibration process, for example, when programming at very high frequencies in some implementations may depend on measured or specific meter stiffness, as determined by the calibration process. In another alternative, a very high frequency can be obtained or determined during the start operation of the meter. For example, a very high frequency may be based on previously stored or user entered values. This may include, for example, a very high frequency, which is based on information previously stored or entered by the user regarding the nature of the multiphase flowing fluid.

Coriolis mass flowmeters and vibrating densitometers require that the flowing fluid move with flowing pipelines during oscillation at the meter’s natural frequency. When foreign material is introduced, this assumption is no longer fulfilled, since a relative motion or separation appears between two or more phases. The model was developed to predict the conditions that are necessary for a successful measurement of the density of a mixture, the specific operating conditions of the meter. An experimentally confirmed fluid model can predict separation effects. The equations to find the separation ratio (A _p / A _f ) and the phase angle (φ) of separation are:

The separation ratio (A _p / A _f ) contains the ratio of the particle amplitude (A _p ) and the amplitude of the flow pipe (A _f ). The particle may contain any foreign material, including gas bubbles, solid particles, or even regions of a different fluid involved within the flowing fluid. The individual values of equation (1) are defined as:

It is assumed that the movement of the flowing fluid is consistent with the movement of the flow pipe. The movement of a bubble or particle is calculated as follows:

(6)Fluid speed

(6)

(7)Particle Speed =

(7)

The inverse Stokes number (δ) is defined as:

(8)

(8)

The inverse Stokes number (δ) takes into account the kinematic viscosity (η) of the flowing fluid, the angular frequency (ω) of the vibration, and the radius (a) of the particle or bubble of the foreign material. The kinematic viscosity (η) contains the dynamic viscosity (μ) divided by the density (ρ) of the fluid, i.e., η = μ / ρ. Foreign material may include entrained gas or entrained solids, as discussed previously. The inverse Stokes number (δ), therefore, can be used to more fully and accurately determine the upper limit of the oscillation frequency than is possible only through setting the frequency.

When the density ratio becomes greater than about 50, the separation ratio depends primarily on the inverse of the Stokes number (δ). This is especially important because all gas / liquid mixtures have high density ratios, usually above 100. Thus, for the most common multiphase flow conditions in a vibratory flow meter, the degree of measurement error depends primarily on the inverse Stokes number (δ). Therefore, if this parameter is very small, the result approaches the inviscid case with a separation ratio of 3: 1, whereas if the parameter is large, the relative motion is limited and the separation ratio approaches 1: 1. The inverse Stokes number (δ) indicates that the balance between the kinematic viscosity of the fluid, particle size, and frequency is important, and not any one of these variables. However, the frequency depends on the design parameters of the meter, while the viscosity and size of particles or bubbles depends on complex and often uncontrollable process conditions.

When the vibratory flowmeter is operating at a high vibrational frequency to operate in a predictable and expected multiphase mode, the inverse Stokes number (δ) can be used to determine if a very high vibrational frequency is high enough. The inverse Stokes number (δ) in some embodiments contains a number lower than about 0.1. The inverse Stokes number (δ) in some embodiments contains a number lower than about 0.01.

The above equations can be used to find the motion of a particle in the vibrating environment of a vibratory flowmeter within approximately plus or minus ten percent accuracy for the amplitude of oscillation and the phase difference for most situations.

Six initial values are needed to solve the above equations for bubble motion: frequency (f) of the vibration response, amplitude (A _f ) of the vibration response, density (ρ _f ) of the fluid, density (ρ _p ) of particles for particles of foreign material involved in the flowing fluid, the dynamic viscosity (μ _f ) of the flowing fluid; and the distribution (a) of the radii of the particles of foreign material involved in the flowing fluid. The frequency (f) of the vibration response and the amplitude (A _f ) of the vibration response can be determined from the vibration response of one or more flow lines (103A, 103B), for example, from a vibration response signal produced by strain gauges (105, 105 ′). The density (ρ _f ) of the fluid can be set by the user, for example, in the case of a known flowing fluid, or can be obtained from a measurement. The density (ρ _p ) of particles can be set by the user or, alternatively, can be determined from the ideal gas law in the case of the gas involved, setting the measured temperature and pressure of the flowing fluid. The dynamic viscosity (μ _f ) can be set by the user, for example, in the case of a known flowing fluid, or can be obtained from a measurement. Particle size distribution (a) may be defined by the user, for example, in the case of a known flowing fluid, or may be obtained from measurements, including acoustic or radiation measurements of foreign material particles or bubbles in a flowing fluid.

High-frequency meters usually did not work well in the presence of gas involved. The main reason for poor performance is that the separation ratio is very large, usually greater than 2: 1. In addition, the effects of the speed of sound lead to additional errors that are predicted by the model:

The angular oscillation frequency (ω) is related to the oscillation frequency by the relation ω = 2πf. The speed of sound of the mixture (c _m ) can be calculated using the well-known equation (see below). The diameter (d) of the flow pipe is known.

The amplitude ratio and phase delay between the flowing fluid and the foreign material involved in it are usually extremely complex functions of particle size, particle density, fluid density, frequency, vibration amplitude of the fluid, and fluid viscosity. Some of these parameters are difficult to measure, including particle sizes, because they depend on many other factors, including the configuration of the pipeline, for example.

In contrast to the viscous model, the inviscid model for particle motion depends only on the densities of both phases, which are often known with reasonable accuracy. In addition, in an inviscid model, motion does not depend on the particle size, and can be displayed as:

A typically inviscid model (i.e., a fluid that does not exhibit viscosity) is not applicable to a vibratory flow meter, since a vibratory flow meter is commonly used to measure viscous fluids. Even water has sufficient viscosity to significantly affect the results. However, it turns out that if the oscillation frequency increases, the physical behavior of the oscillating flow is closer to the inviscid case, even for a fluid with a certain viscosity. If the oscillation frequency is very high, for example 2000 Hz, then the inviscid model is applicable and the gas bubble moves approximately 3 times further than the fluid, without phase delay. This is usually a bad situation for measurements. Greater separation means a larger density and mass flow error. However, a significant advantage of working at this high frequency is that the movements of the bubble and particles depend only on the density ratio. The movement of a foreign material, gas or solid does not depend on a size distribution that is usually unknown and which may not be possible to determine.

The density error due to separation for arbitrary separation relations can be predicted in accordance with the equation:

At high frequencies, SOS / compressibility effects will be significant and added, leading to the equation:

The above equation describes the density error as a deviation from the true density of the mixture due to the combined effects of SOS / compressibility and separation. If all six input parameters for the equations of particle motion are known, the separation ratio (A _p / A _f ) can be calculated in general for any frequency. However, if the meter operates at a very high frequency, then the separation ratio (A _p / A _f ), as is known, is approximately three for gas bubbles in a liquid, that is, the bubble will travel a distance three times larger than the flowing fluid, although without any or phase delay. Therefore, for a satisfactory high frequency of oscillations, equation (13) takes the form:

Now the equation depends only on quantities that are well known for many processes. Three other equations are needed to solve them together and determine four unknowns (φ _f , φ _p , ρ _mix , c _mix ), where (φ _f ) is the fraction of liquid, (φ _p ) is the fraction of particle / gas, (ρ _mix ) is the density of the multiphase flowing fluid (that is, the mixture) and (c _mix ) is the speed of sound in the mixture.

Equations (14-17) can be solved together for volume fractions, mixture density and sound velocity of the mixture. Thus, a high vibration frequency, gas fraction and liquid fraction can be determined. From certain gas and liquid fractions, the flow rates of these two components can be estimated either by mass or by volume (in this case, it is assumed that there are no lagging bubbles and it is assumed that instead the bubble moves down the pipeline along the same velocity as the liquid). These costs would otherwise be unknown, since a Coriolis meter or densitometer measures the density of a mixture even when there are no separation effects or SOS / compressibility effects. The calculation of the mass or volumetric flow rate of the liquid is desirable, since the user usually only needs to measure the liquid. This calculation of costs comes from the joint resolution of two additional linearly independent equations:

Where (dm _f / dt) is the mass flow rate of the flowing fluid, (dm _p / dt) is the mass flow rate of foreign material particles and (dm _mix / dt) is the mass flow rate of the multiphase mixture. The above equation does not imply a lag of foreign material relative to the flowing fluid.

You can force the flow pipe to oscillate at additional resonant frequencies of the bending modes to determine the phase fractions for a mixture that includes more than two components. For example, consider the following mixture of oil, water, and gas. The system of solvable equations with five unknowns (φ _g , φ _w , φ ₀ , ρ _mix , c _mix ) contains the following equations:

There are indeed five equations, since the last equation is applicable to both the low-frequency bending mode and the high-frequency bending mode. The indices indicate oil (o), water (w) and gas (g).

In this case, since there are vibrations at both low and high frequencies, the size of the gas bubble must be very small in order to avoid bubble lag and separation. Alternatively, the meter can oscillate at a very low-frequency and very high-frequency bending mode at the same time, and the system of equations can be resolved by appropriate consideration of various forms of equation (23).

In many cases, the bubble size is not small enough to make these assumptions (especially with a meter that uses moderate to high vibration frequencies). However, separation can be added back to the equation so that the method works in a general way, using equation (13) for high-frequency and low-frequency modes. As always, the problem is what exactly to use for the separation relation (A _p / A _f ), assuming that it cannot be calculated explicitly. At least in the case of the high-frequency mode, the separation ratio (A _p / A _f ) will be almost or approximately equal to three. In the case of the low-frequency mode, it can be assumed that the frequency was low enough to neglect separation, that is, when the separation ratio (A _p / A _f ) is approximately unity. Alternatively, an intermediate value may be expected and used.

Claims (24)

1. A vibration meter (100) with a very high vibration frequency, comprising:
a flowmeter assembly (10) including one or more flow lines (103 A, 103B), with a flowmeter assembly (10) configured to generate a response at a very high frequency that is higher than a predetermined maximum separation frequency for the flowing fluid, regardless of the size of the foreign material or composition of foreign material, the separation ratio (A _p / A _f ) being approximately 3: 1 for the involved gas at a very high frequency and approximately equal to 3 / (l + (2 · ρ _p / ρ _f )) for the solids involved at a very high frequency, wherein the separation ratio (A _p / A _f ) is the ratio of the particle amplitude (A _p ) to the fluid amplitude (A _f ), where ρ _p is the particle density of the foreign material and ρ _f is the density of the flowing fluid ; and
meter electronics (20) connected to the flowmeter assembly (10) and configured to receive a very high frequency vibration response and generate one or more flow measurements from it. 2. A vibration meter (100) with a very high vibration frequency according to claim 1, wherein the meter electronics (20) is configured so that the viscosity is effectively zero relative to particle movement for the flowing fluid at a very high frequency. 3. A vibration meter (100) with a very high vibration frequency according to claim 1, with a very high frequency vibration response corresponding to the inverse of the Stokes number (δ), which is less than about 0.1. 4. A vibration meter (100) with a very high vibration frequency according to claim 1, with a very high frequency that is above about 1500 Hertz (Hz). 5. A vibration meter (100) with a very high frequency of vibration according to claim 1, with a very high frequency, which is above about 2000 Hertz (Hz). 6. A vibration meter (100) with a very high frequency of vibration according to claim 1, wherein one or more flow lines (103A, 103B) are configured to achieve a very high frequency by configuring one or more of: stiffness of the flow pipe, length of the flow pipe, characteristic ratio flow pipe, flow pipe material, flow pipe thickness, flow pipe shape, flow pipe geometry or one or more positions of vibrating units. 7. A vibration meter (100) with a very high vibration frequency according to claim 1, with a vibration meter with a very high vibration frequency configured to operate on the first bending mode. 8. A vibration meter (100) with a very high vibration frequency according to claim 1, with a vibration meter with a very high vibration frequency configured to operate at a second or higher frequencies of the bending modes. 9. The mode of operation of a vibratory flow meter with a very high vibration frequency, the method comprising:
vibration of one or more flow lines of a vibratory flowmeter with a very high vibration frequency at a very high frequency, the very high frequency being higher than the predetermined maximum separation frequency for the flowing fluid, regardless of the size of the foreign material or the composition of the foreign material, and the separation ratio (A _p / A _f ) is approximately 3: 1 for entrained gas at the very high frequency and is approximately equal to the value of 3 / (l + (2 · ρ _p / ρ _f)) for entrained solids at the very high often e, the decoupling ratio (A _p / A _f) is an amplitude ratio of the particle (A _p) to the fluid amplitude (A _f), where ρ _p is the density of the particles of foreign material, and ρ _f is the density of the flow fluid;
receiving a very high-frequency vibration response; and
generating one or more flow measurements from a very high frequency vibrational response. 10. The method according to claim 9 with a vibratory flowmeter with a very high frequency of vibration, configured so that the viscosity is effectively zero relative to the movement of particles for the flowing fluid at a very high frequency. 11. The method according to claim 9 with a very high frequency vibrational response corresponding to the inverse of the Stokes number (δ), which is less than about 0.1. 12. The method according to claim 9 with a very high frequency, which is above approximately 1500 Hertz (Hz). 13. The method according to claim 9 with a very high frequency, which is above approximately 2000 Hertz (Hz). 14. The method according to claim 9, wherein one or more flow lines of the vibratory flow meter with a very high vibration frequency are configured to achieve a very high frequency by configuring one or more of: rigidity of the flow pipe, length of the flow pipe, characteristic ratio of the flow pipe, material of the flow pipe, the thickness of the flow pipe, the shape of the flow pipe, the geometry of the flow pipe or one or more positions of the vibration units. 15. The method according to claim 9 with a vibratory flow meter with a very high vibration frequency configured to operate on the first bending mode. 16. The method according to claim 9 with a vibratory flowmeter with a very high vibration frequency, configured to operate at higher frequencies of the bending modes. 17. A method for constructing a vibratory flow meter with a very high vibration frequency, the method comprising:
determining a predetermined very high frequency for the vibratory flow meter based on at least the expected flowing fluid, the very high frequency being higher than the preset maximum separation frequency for the flowing fluid, regardless of the size of the foreign material or the composition of the foreign material, the separation ratio (A _p / A _f ) is approximately 3: 1 for the involved gas at a very high frequency and approximately equal to 3 / (l + (2 · ρ _p / ρ _f )) for the involved solids at a very high frequency, and times the dividing ratio (A _p / A _f ) is the ratio of the particle amplitude (A _p ) to the fluid amplitude (A _f ), wherein ρ _p is the particle density of the foreign material and ρ _f is the density of the flowing fluid;
Configuring a vibratory flowmeter with a very high vibration frequency to operate at a very high frequency; and
design of a vibratory flowmeter with a very high vibration frequency. 18. The method according to 17, and the meter electronics is configured so that the viscosity is effectively zero relative to the movement of the particles for the flowing fluid at a very high frequency. 19. The method according to 17 with a very high frequency vibrational response corresponding to the inverse of the Stokes number (δ), which is less than about 0.1. 20. The method according to 17 with a very high frequency, which is above approximately 1500 Hertz (Hz). 21. The method according to claim 20 with a very high frequency, which is higher than approximately 2000 Hertz (Hz). 22. The method according to 17, and one or more flow pipes are configured to achieve a very high frequency by configuring one or more of: the rigidity of the flow pipe, the length of the flow pipe, the characteristic ratio of the flow pipe, the material of the flow pipe, the thickness of the flow pipe, the shape of the flow pipe, the geometry of the flow pipe, or one or more positions of the vibration units. 23. The method according to claim 17 with a vibratory flowmeter with a very high vibration frequency configured to operate on the first bending mode. 24. The method of claim 17 with a vibration meter with a very high vibration frequency configured to operate at a second or higher frequencies of the bending modes.

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